A wireless communication system has been widely developed to provide various kinds of communication services such as voice and data. Generally, the wireless communication system is a multiple access system that can support communication with multiple users by sharing available system resources (bandwidth, transmission power, etc.). Examples of the multiple access system include a code division multiple access (CDMA) system, a frequency division multiple access (FDMA) system, a time division multiple access (TDMA) system, an orthogonal frequency division multiple access (OFDMA) system, and a single carrier frequency division multiple access (SC-FDMA) system.
Regarding to a network security, a spoofing attack is a situation in which one person or program successfully masquerades as another by falsifying data and thereby gaining an illegitimate advantage.
As one of kinds of the spoofing attack, a caller identifier (ID) spoofing exists. That is, public telephone networks often provide caller ID information, which includes the caller's name and number, with each call. However, some technologies (especially in Voice over IP (VoIP) networks) allow callers to forge Caller ID information and present false names and numbers. Gateways between networks that allow such spoofing and other public networks then forward that false information. Since spoofed calls can originate from other countries, the laws in the receiver's country may not apply to the caller. This limits laws' effectiveness against the use of spoofed Caller ID information to further a scam.